"We would never want a patient who's not going to see a benefit to take it and tell everyone it doesn't work," she said.

Lobbying by Sprout Pharmaceuticals was backed by the women's rights group Even the Score, which has accused the FDA of gender bias by approving a number of drugs treating erectile dysfunction in men without passing an equivalent for women.

Originally the drug was produced by German company Boehringer Ingelheim. Sprout bought the drug from that company after it was turned down by the FDA.